In typical ball or roller bearings, loads are transmitted from one bearing race through a series of rolling elements to a second bearing race. These rolling elements are in sliding contact with each other or with a cage, and the resulting friction is undesireable in that it causes wear and necessitates the provision of lubrication and internal clearances. In some bearings sliding friction is eliminated by providing one or two additional sets of rolling elements, as in U.S. Pat. No. 116,795 issued to B. C. Baker, U.S. Pat. No. 413,446 issued to R. W. Hent and U.S. Pat. No. 3,365,254 issued to A. L. Nasvytis; but these bearings are either excessively complex or their rotating elements move at excessive speeds.